Chip package with interposer substrate and method for forming the same

ABSTRACT

A method for forming a chip package is provided. The method includes disposing a chip over a redistribution structure. The redistribution structure includes a first insulating layer and a first wiring layer, and the first wiring layer is in the first insulating layer and electrically connected to the chip. The method includes bonding an interposer substrate to the redistribution structure through a conductive structure. The chip is between the interposer substrate and the redistribution structure. The interposer substrate has a recess adjacent to the redistribution structure. A first portion of the chip is in the recess. The interposer substrate includes a substrate and a conductive via structure, and the conductive via structure passes through the substrate and is electrically connected to the first wiring layer through the conductive structure.

PRIORITY CLAIM AND CROSS-REFERENCE

This Application claims the benefit of U.S. Provisional Application No. 62/579,241, filed on Oct. 31, 2017, and entitled “Fan Out Package with interposer”, the entirety of which is incorporated by reference herein.

BACKGROUND

Semiconductor devices are used in a variety of electronic applications, such as personal computers, cell phones, digital cameras, and other electronic equipment. Semiconductor devices are typically fabricated by sequentially depositing insulating layers or dielectric layers, conductive layers, and semiconductor layers over a semiconductor substrate, and patterning the various material layers using photolithography processes and etching processes to form circuit components and elements thereon.

Many integrated circuits are typically manufactured on a semiconductor wafer. The semiconductor wafer may be singulated into dies. The dies may be packaged, and various technologies have been developed for packaging.

BRIEF DESCRIPTION OF THE DRAWINGS

Aspects of the present disclosure are best understood from the following detailed description when read with the accompanying figures. It should be noted that, in accordance with standard practice in the industry, various features are not drawn to scale. In fact, the dimensions of the various features may be arbitrarily increased or reduced for clarity of discussion.

FIGS. 1A-1J are cross-sectional views of various stages of a process for forming a chip package, in accordance with some embodiments.

FIG. 1D-1 is a top view of the chip package of FIG. 1D, in accordance with some embodiments.

FIG. 2 is a cross-sectional view of a chip package, in accordance with some embodiments.

FIGS. 3A-3B are cross-sectional views of various stages of a process for forming a chip package, in accordance with some embodiments.

FIG. 4 is a cross-sectional view of a chip package, in accordance with some embodiments.

FIG. 5 is a cross-sectional view of a chip package, in accordance with some embodiments.

FIG. 6 is a cross-sectional view of a chip package, in accordance with some embodiments.

FIGS. 7A-7B are cross-sectional views of various stages of a process for forming a chip package, in accordance with some embodiments.

FIG. 8A is a cross-sectional view of a chip package, in accordance with some embodiments.

FIG. 8B is a top view of the interposer substrate of the chip package of FIG. 8A, in accordance with some embodiments.

FIG. 9A is a cross-sectional view of a chip package, in accordance with some embodiments.

FIG. 9B is a top view of the interposer substrate of the chip package of FIG. 9A, in accordance with some embodiments.

FIG. 10A is a cross-sectional view of a chip package, in accordance with some embodiments.

FIG. 10B is a top view of the interposer substrate of the chip package of FIG. 10A, in accordance with some embodiments.

FIG. 11 is a cross-sectional view of a chip package, in accordance with some embodiments.

FIG. 12 is a cross-sectional view of a chip package, in accordance with some embodiments.

FIG. 13 is a cross-sectional view of a chip package, in accordance with some embodiments.

FIGS. 14A-14D are cross-sectional views of various stages of a process for forming a chip package, in accordance with some embodiments.

FIG. 15 is a cross-sectional view of a chip package, in accordance with some embodiments.

DETAILED DESCRIPTION

The following disclosure provides many different embodiments, or examples, for implementing different features of the subject matter provided. Specific examples of components and arrangements are described below to simplify the present disclosure. These are, of course, merely examples and are not intended to be limiting. For example, the formation of a first feature over or on a second feature in the description that follows may include embodiments in which the first and second features are formed in direct contact, and may also include embodiments in which additional features may be formed between the first and second features, such that the first and second features may not be in direct contact. In addition, the present disclosure may repeat reference numerals and/or letters in the various examples. This repetition is for the purpose of simplicity and clarity and does not in itself dictate a relationship between the various embodiments and/or configurations discussed.

Furthermore, spatially relative terms, such as “beneath,” “below,” “lower,” “above,” “upper” and the like, may be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures. The spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. The apparatus may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein may likewise be interpreted accordingly. It should be understood that additional operations can be provided before, during, and after the method, and some of the operations described can be replaced or eliminated for other embodiments of the method.

Other features and processes may also be included. For example, testing structures may be included to aid in the verification testing of the 3D packaging or 3DIC devices. The testing structures may include, for example, test pads formed in a redistribution layer or on a substrate that allows the testing of the 3D packaging or 3DIC, the use of probes and/or probe cards, and the like. The verification testing may be performed on intermediate structures as well as the final structure. Additionally, the structures and methods disclosed herein may be used in conjunction with testing methodologies that incorporate intermediate verification of known good dies to increase the yield and decrease costs.

FIGS. 1A-1J are cross-sectional views of various stages of a process for forming a chip package, in accordance with some embodiments. As shown in FIG. 1A, a carrier substrate 110 is provided, in accordance with some embodiments. The carrier substrate 110 is configured to provide temporary mechanical and structural support during subsequent processing steps, in accordance with some embodiments. The carrier substrate 110 includes glass, silicon, silicon oxide, aluminum oxide, metal, a combination thereof, and/or the like, in accordance with some embodiments. The carrier substrate 110 includes a metal frame, in accordance with some embodiments.

As shown in FIG. 1A, a redistribution structure 120 is formed over the carrier substrate 110, in accordance with some embodiments. The formation of the redistribution structure 120 includes forming an insulating layer 121 over the carrier substrate 110; forming conductive pads 122 over the insulating layer 121 and in through holes 121 a of the insulating layer 121; forming an insulating layer 123 over the insulating layer 121 and the conductive pads 122; forming a wiring layer 124 over the insulating layer 123 and in through holes 123 a of the insulating layer 123; forming an insulating layer 125 over the insulating layer 123 and the wiring layer 124; forming a wiring layer 126 over the insulating layer 125 and in through holes 125 a of the insulating layer 125; forming an insulating layer 127 over the insulating layer 125 and the wiring layer 126; and forming conductive pads 128 a and 128 b over the insulating layer 127 and in through holes 127 a of the insulating layer 127. The conductive pad 128 a is wider than the conductive pad 128 b, in accordance with some embodiments. The conductive pads 128 a surround the conductive pads 128 b, in accordance with some embodiments.

In some embodiments, the conductive pads 122 are in direct contact with the carrier substrate 110. In some other embodiments (not shown), the conductive pads 122 are spaced apart from the carrier substrate 110. The wiring layers 124 and 126 are electrically connected to each other, in accordance with some embodiments. The conductive pads 122, 128 a, and 128 b are electrically connected to the wiring layers 124 and 126, in accordance with some embodiments.

The insulating layers 121, 123, 125, and 127 are made of an insulating material such as a polymer material (e.g., polybenzoxazole, polyimide, or a photosensitive material), nitride (e.g., silicon nitride), oxide (e.g., silicon oxide), silicon oxynitride, or the like, in accordance with some embodiments. The wiring layers 124 and 126 and the conductive pads 122, 128 a and 128 b are made of a conductive material, such as metal (e.g. copper, aluminum, or tungsten), in accordance with some embodiments.

As shown in FIG. 1B, dam structures 130 are formed over the redistribution structure 120, in accordance with some embodiments. For the sake of simplicity, FIGS. 1B-1E only show one of the dam structures 130, in accordance with some embodiments. The dam structure 130 has an opening 132, in accordance with some embodiments. The dam structure 130 is a ring structure, in accordance with some embodiments. The dam structure 130 continuously surrounds the conductive pads 128 b, in accordance with some embodiments.

The dam structure 130 is made of a polymer material or a metal material, in accordance with some embodiments. The formation of the dam structure 130 includes forming a dam material layer over the redistribution structure 120; and performing a photolithography process and an etching process on the dam material layer. If the dam structure 130 is made of a photosensitive material, the formation of the dam structure 130 includes forming a dam material layer over the redistribution structure 120; and performing a photolithography process. In some embodiments, the dam structures 130 are not formed.

As shown in FIG. 1C, chips 140 are bonded to the redistribution structure 120 through conductive bumps 150, in accordance with some embodiments. For the sake of simplicity, FIGS. 1C-1E only show one of the chips 140, in accordance with some embodiments. The chip 140 is over or in the opening 132 of the dam structure 130, in accordance with some embodiments.

The chip 140 has a substrate 142 and conductive pads 144, in accordance with some embodiments. The substrate 142 has a surface 142 a facing the redistribution structure 120, in accordance with some embodiments. The conductive pads 144 are over the surface 142 a, in accordance with some embodiments.

In some embodiments, electronic elements (not shown) are formed on or in the substrate 142. The electronic elements include active elements (e.g. transistors, diodes, or the like) and/or passive elements (e.g. resistors, capacitors, inductors, or the like). The conductive pads 144 are electrically connected to the electronic elements, in accordance with some embodiments.

In some embodiments, the substrate 142 is made of at least an elementary semiconductor material including silicon or germanium in a single crystal, polycrystal, or amorphous structure. In some other embodiments, the substrate 142 is made of a compound semiconductor, such as silicon carbide, gallium arsenide, gallium phosphide, indium phosphide, indium arsenide, an alloy semiconductor, such as SiGe, or GaAsP, or a combination thereof.

The substrate 142 may also include multi-layer semiconductors, semiconductor on insulator (SOI) (such as silicon on insulator or germanium on insulator), or a combination thereof. The conductive pads 144 is made of a conductive material, such as metal (e.g., copper, aluminum, nickel, or combinations thereof), in accordance with some embodiments.

The conductive bumps 150 are between the conductive pads 128 b and 144 to electrically connect the conductive pads 128 b to the conductive pads 144, in accordance with some embodiments. The conductive bumps 150 are in the opening 132, in accordance with some embodiments. The conductive bumps 150 are made of a solder material, such as Sn and Ag or another suitable conductive material (e.g., gold), in accordance with some embodiments. The conductive bumps 150 are solder balls, in accordance with some embodiments.

FIG. 1D-1 is a top view of the chip package of FIG. 1D, in accordance with some embodiments. As shown in FIGS. 1D and 1D-1, an underfill layer 160 is formed between the chip 140 and the redistribution structure 120, in accordance with some embodiments. The dam structure 130 continuously surrounds the entire underfill layer 160 to prevent the underfill layer 160 from extending onto the conductive pads 128 a, in accordance with some embodiments. The underfill layer 160 is made of an insulating material, such as a polymer material or a molding compound material consisting of epoxy and filler material, in accordance with some embodiments.

As shown in FIG. 1E, interposer substrates 170 are bonded to the redistribution structure 120 through conductive structures 180, in accordance with some embodiments. For the sake of simplicity, FIG. 1E only shows one of the interposer substrates 170, in accordance with some embodiments. The chip 140 is between the interposer substrate 170 and the redistribution structure 120, in accordance with some embodiments. The interposer substrate 170 has a recess R adjacent to the redistribution structure 120, in accordance with some embodiments. The recess R faces the redistribution structure 120, in accordance with some embodiments. In some embodiments, a portion of the chip 140 is in the recess R.

The interposer substrate 170 includes a substrate 172, conductive pads 173 a and 173 b, conductive via structures 174, insulating layers 175, 176, and 178, and wiring layers (not shown), in accordance with some embodiments. The substrate 172 has two opposite surfaces 172 a and 172 b, in accordance with some embodiments. The surface 172 a faces the redistribution structure 120, in accordance with some embodiments.

The substrate 172 is made of a fiber material, a polymer material, a semiconductor material, a glass material, a metal material, or another suitable material. The fiber material includes, for example, a glass fiber material. The semiconductor material includes, for example, silicon or germanium.

The conductive pads 173 a are over the surface 172 a, in accordance with some embodiments. The conductive pads 173 b are over the surface 172 b, in accordance with some embodiments. The conductive via structures 174 pass through the substrate 172, in accordance with some embodiments. The conductive via structures 174 are between and connected to the conductive pads 173 a and 173 b, in accordance with some embodiments.

The wiring layers (not shown) are formed over the surface 172 b and are electrically connected to the conductive pads 173 b and the conductive via structures 174, in accordance with some embodiments. The wiring layers (not shown) are further formed over the surface 172 a and are electrically connected to the conductive pads 173 a and the conductive via structures 174, in accordance with some embodiments. The conductive via structures 174, the conductive pads 173 a and 173 b, and the wiring layers are made of a conductive material, such as copper, aluminum, or tungsten, in accordance with some embodiments.

The insulating layer 175 is between the conductive via structures 174 and the substrate 172, between the conductive pads 173 a and the substrate 172, and between the conductive pads 173 b and the substrate 172, in accordance with some embodiments. The conductive pads 173 a and 173 b and the conductive via structures 174 are electrically insulated from the substrate 172 by the insulating layer 175, in accordance with some embodiments.

The insulating layer 176 is formed over the surface 172 a, in accordance with some embodiments. The insulating layer 176 has openings 176 a respectively exposing the conductive pads 173 a thereover, in accordance with some embodiments. The insulating layer 178 is formed over the surface 172 b, in accordance with some embodiments.

The insulating layer 178 has openings 178 a respectively exposing the conductive pads 173 b thereunder, in accordance with some embodiments. The recess R passes through the insulating layer 176 and extends into the substrate 172, in accordance with some embodiments. The insulating layers 175, 176, and 178 are made of an insulating material, such as oxide (e.g., silicon oxide), in accordance with some embodiments.

The interposer substrate 170 may further include conductive layers 179. The conductive layers 179 are respectively formed over the conductive pads 173 b, in accordance with some embodiments. The conductive layers 179 are made of a surface finish material (e.g., nickel, palladium, and/or gold) or a solder material, such as Sn and Ag or another suitable conductive material, in accordance with some embodiments.

In some other embodiments, as shown in FIG. 2, the substrate 172 is made of an insulating material, and the insulating layer 175 is not formed. As shown in FIG. 2, the interposer substrate 170 further includes wiring layers 201 formed in the substrate 172, in accordance with some embodiments.

The wiring layers 201 electrically connect the conductive pads 173 b (e.g., the conductive pads 173 b over the recess R) to the conductive via structures 174, in accordance with some embodiments. The interposer substrate 170 of FIG. 1E may be replaced by the interposer substrate 170 of FIG. 2.

Referring back to FIG. 1E, the conductive structures 180 are formed between the conductive pads 173 a and 128 a, in accordance with some embodiments. The conductive structures 180 electrically connect the conductive pads 173 a to the conductive pads 128 a, in accordance with some embodiments. The conductive structures 180 are conductive bumps or conductive pillars, in accordance with some embodiments. The conductive structures 180 are made of a conductive material, such as a metal material (e.g., copper) or a solder material (e.g., Sn and Ag), in accordance with some embodiments.

As shown in FIG. 1F, a release film 190 is formed over the interposer substrates 170 to cover the conductive layers 179 and the conductive pads 173 b, in accordance with some embodiments. The release film 190 is used to prevent the conductive layers 179 and the conductive pads 173 b from being covered by a molding layer formed in the subsequent process, in accordance with some embodiments. The release film 190 is made of a polymer material or another suitable material.

Thereafter, as shown in FIG. 1F, a molding layer 210 is formed between the release film 190, the interposer substrates 170, the redistribution structure 120, and the chips 140, in accordance with some embodiments. In some embodiments, a thermal process is performed on the molding layer 210 to cure the molding layer 210. The molding layer 210 surrounds the interposer substrates 170, the chips 140, the conductive bumps 150, the underfill layer 160, the conductive structures 180, and the dam structures 130, in accordance with some embodiments. The molding layer 210 is made of a polymer material or another suitable insulating material.

As shown in FIG. 1G, the release film 190 is removed, in accordance with some embodiments. As shown in FIG. 1G, a trench 212 is formed in the molding layer 210, in accordance with some embodiments. The trench 212 passes through the molding layer 210 between the interposer substrates 170 and between the conductive structures 180 under different interposer substrates 170, in accordance with some embodiments.

The trench 212 divides the molding layer 210 into portions 214, in accordance with some embodiments. The portions 214 are spaced apart from each other, in accordance with some embodiments. Each of the portions 214 surrounds one of the interposer substrates 170 and the chip 140 under the one of the interposer substrates 170, in accordance with some embodiments. The trench 212 is formed using a cutting process, in accordance with some embodiments.

As shown in FIG. 1H, the carrier substrate 110 is removed, in accordance with some embodiments. As shown in FIG. 1H, the redistribution structure 120 is flipped upside down, in accordance with some embodiments. As shown in FIG. 1H, the redistribution structure 120 and the interposer substrates 170 are disposed over a carrier substrate 220, in accordance with some embodiments.

As shown in FIG. 1H, the insulating layer 121 is removed, in accordance with some embodiments. In some other embodiments (not shown), the insulating layer 121 is partially removed to expose the conductive pads 122. As shown in FIG. 1H, conductive bumps 230 are respectively formed over the conductive pads 122, in accordance with some embodiments. The conductive bumps 230 are made of a solder material, such as Sn and Ag or another suitable conductive material, in accordance with some embodiments.

As shown in FIGS. 1H and 1I, a sawing process is performed on the redistribution structure 120 between the interposer substrates 170 to cut through the redistribution structure 120, in accordance with some embodiments. The redistribution structure 120 is cut into portions 129 spaced apart from each other, in accordance with some embodiments.

After the sawing process, the carrier substrate 220 is removed, in accordance with some embodiments. After the sawing process, chip packages 100 are substantially formed, in accordance with some embodiments. For the sake of simplicity, FIG. 1I only shows one of the chip packages 100, in accordance with some embodiments.

As shown in FIG. 1I, the chip package 100 has the portion 129 of the redistribution structure 120, the chip 140, the interposer substrate 170, the portion 214 of the molding layer 210, and the conductive bumps 150 and 230, in accordance with some embodiments. The interposer substrate 170 has a thickness T1 ranging from about 50 μm to about 300 μm, in accordance with some embodiments. The recess R has a depth D1 ranging from about 20 μm to about 270 μm, in accordance with some embodiments.

As shown in FIG. 1J, a package structure 300 is bonded to the interposer substrate 170 through conductive bumps 240, in accordance with some embodiments. The conductive bumps 240 are between the package structure 300 and the interposer substrate 170, in accordance with some embodiments. The conductive layers 179 are merged into the conductive bumps 240, in accordance with some embodiments.

The package structure 300 is electrically connected to the wiring layer 124 and 126 of the redistribution structure 120 through the conductive bumps 240, the interposer substrate 170, and the conductive structures 180, in accordance with some embodiments. The package structure 300 includes a memory device (e.g., a dynamic random access memory device), a passive device, a logic device, a radio frequency (RF) device, or another suitable device.

The package structure 300 includes a redistribution structure 310, a chip 320, conductive bumps 330, an underfill layer 340, and a molding layer 350, in accordance with some embodiments. The redistribution structure 310 includes an insulating layer 312, conductive pads 314 and 316, and wiring layers 318, in accordance with some embodiments. The insulating layer 312 may be a multilayer structure or a single layer structure.

The wiring layers 318 and portions of the conductive pads 314 and 316 are in the insulating layer 312, in accordance with some embodiments. The wiring layers 318 are electrically connected to the conductive pads 314 and 316, in accordance with some embodiments. The insulating layer 312 is made of an insulating material such as a polymer material (e.g., polybenzoxazole, polyimide, or a photosensitive material), nitride (e.g., silicon nitride), oxide (e.g., silicon oxide), silicon oxynitride, or the like, in accordance with some embodiments. The wiring layers 318 and the conductive pads 314 and 316 are made of a conductive material, such as metal (e.g. copper, aluminum, or tungsten), in accordance with some embodiments.

The chip 320 is bonded to the redistribution structure 310 through the conductive bumps 330, in accordance with some embodiments. The chip 320 has a substrate 322 and conductive pads 324, in accordance with some embodiments. The substrate 322 has a surface 322 a facing the redistribution structure 310, in accordance with some embodiments. The conductive pads 324 are over the surface 322 a, in accordance with some embodiments.

In some embodiments, electronic elements (not shown) are formed on or in the substrate 322. The electronic elements include active elements (e.g. transistors, diodes, or the like) and/or passive elements (e.g. resistors, capacitors, inductors, or the like). The conductive pads 324 are electrically connected to the electronic elements, in accordance with some embodiments.

In some embodiments, the substrate 322 is made of at least an elementary semiconductor material including silicon or germanium in a single crystal, polycrystal, or amorphous structure. In some other embodiments, the substrate 322 is made of a compound semiconductor, such as silicon carbide, gallium arsenide, gallium phosphide, indium phosphide, indium arsenide, an alloy semiconductor, such as SiGe, or GaAsP, or a combination thereof.

The substrate 322 may also include multi-layer semiconductors, semiconductor on insulator (SOI) (such as silicon on insulator or germanium on insulator), or a combination thereof. The conductive pads 324 is made of a conductive material, such as metal (e.g., copper or aluminum), in accordance with some embodiments.

The conductive bumps 330 are between and electrically connected to the conductive pads 314 and 324, in accordance with some embodiments. The conductive bumps 330 are made of a solder material, such as Sn and Ag or another suitable conductive material, in accordance with some embodiments.

The underfill layer 340 is formed between the chip 320 and the redistribution structure 310, in accordance with some embodiments. The underfill layer 340 is made of an insulating material, such as a polymer material, in accordance with some embodiments. The molding layer 350 is formed over the redistribution structure 310 to cover the chip 320 and the underfill layer 340, in accordance with some embodiments. The molding layer 350 is made of a polymer material or another suitable insulating material.

As shown in FIG. 1J, an underfill layer 360 is formed between the redistribution structure 310 and the interposer substrate 170 (or the molding layer 210), in accordance with some embodiments. The underfill layer 360 surrounds the conductive bumps 240, in accordance with some embodiments. The underfill layer 360 is made of an insulating material, such as a polymer material, in accordance with some embodiments. In this step, a chip package C1 is substantially formed, in accordance with some embodiments.

The chip package C1 includes the chip packages 100 and 300, the conductive bumps 240, and the underfill layer 360, in accordance with some embodiments. In the chip package C1, the chip 140 is partially or entirely positioned in the interposer substrate 170, in accordance with some embodiments. Therefore, the total thickness T2 of the chip package C1 is decreased, in accordance with some embodiments.

The rigidity of the interposer substrate 170 is greater than the rigidity of the molding layer 210, in accordance with some embodiments. Therefore, the interposer substrate 170 may decrease the warpage of the chip package 100. As a result, the bonding yield between the chip packages 100 and 300 is improved, in accordance with some embodiments. In some embodiments, the interposer substrate 170 enhances the stiffness and bending strength of the chip package 100.

The interposer substrate 170 is a rigid substrate, in accordance with some embodiments. Therefore, the interposer substrate 170 (including the conductive pads 173 b) is substantially not affected by the stress caused by thermal expansion mismatch between the molding layer 210 and the chip 140, in accordance with some embodiments. As a result, the bonding yield between the conductive pads 173 b and the conductive bumps 240 is improved, in accordance with some embodiments.

FIGS. 3A-3B are cross-sectional views of various stages of a process for forming a chip package, in accordance with some embodiments. After the step of FIG. 1D is performed, as shown in FIG. 3A, an adhesive layer A is formed over a top surface 142 b of the substrate 142 of the chip 140, in accordance with some embodiments. The adhesive layer A is a film, a glue layer, or a paste layer, in accordance with some embodiments.

The adhesive layer A is made of a polymer material or a high thermal conductivity material, in accordance with some embodiments. The high thermal conductivity material has a thermal conductivity (k) greater than about 1 Wm⁻¹K⁻¹, in accordance with some embodiments. The high thermal conductivity material includes A1 ₂O₃ and/or graphene, in accordance with some embodiments. The adhesive layer A is formed using a coating process, a lamination process, or a deposition process, in accordance with some embodiments.

As shown in FIG. 3B, the steps of FIGS. 1E-1J are performed, in accordance with some embodiments. As shown in FIG. 3B, a chip package C3 is formed, in accordance with some embodiments. The chip package C3 is similar to the chip package C1 of FIG. 1J, except that the chip package C3 further has the adhesive layer A, in accordance with some embodiments. The adhesive layer A is in direct contact with the interposer substrate 170 (or the substrate 172) and the chip 140, in accordance with some embodiments.

The adhesive layer A is used to bond the interposer substrate 170 to the chip 140, in accordance with some embodiments. The adhesive layer A is used to dissipate the heat generated from the chip 140 to the interposer substrate 170, in accordance with some embodiments.

FIG. 4 is a cross-sectional view of a chip package C4, in accordance with some embodiments. As shown in FIG. 4, the chip package C4 is similar to the chip package Cl of FIG. 1J, except that the recess R of the chip package C4 does not pass through the insulating layer 176, in accordance with some embodiments. Therefore, the recess R does not extend into the substrate 172, in accordance with some embodiments.

The interposer 170 has wiring layers 410 and 420 and conductive pads 430 and 440, in accordance with some embodiments. The wiring layers 410 are in the insulating layer 176 and connected to the conductive pads 430, in accordance with some embodiments. The insulating layer 176 covers portions of the conductive pads 430, in accordance with some embodiments. The wiring layers 410, the conductive pads 430, and the insulating layer 176 together form a wiring structure WR1, in accordance with some embodiments.

The recess R does not pass through the wiring structure WR1, in accordance with some embodiments. The conductive structures 180 are connected to the conductive pads 430, in accordance with some embodiments. The wiring layers 420 are in the insulating layer 178 and connected to the conductive pads 440, in accordance with some embodiments. The insulating layer 178 covers portions of the conductive pads 440, in accordance with some embodiments. The wiring layers 420, the conductive pads 440, and the insulating layer 178 together form a wiring structure WR2, in accordance with some embodiments.

The conductive bumps 240 are connected to the conductive pads 440, in accordance with some embodiments. The conductive pads 440 and the wiring layers 420 are electrically connected to the conductive pads 430 and the wiring layers 410 through the conductive via structures 174, in accordance with some embodiments. The interposers 170 of FIGS. 1E-1J and 3B may include the wiring structures WR1 and WR2 according to requirements.

FIG. 5 is a cross-sectional view of a chip package C5, in accordance with some embodiments. As shown in FIG. 5, the chip package C5 is similar to the chip package C4 of FIG. 4, except that the recess R of the chip package C5 passes through the wiring structure WR1 and the substrate 172, in accordance with some embodiments. The wiring structure WR2 further has a conductive layer 510 in the insulating layer 178, in accordance with some embodiments. The recess R exposes the conductive layer 510, in accordance with some embodiments.

The conductive layer 510 is over the chip 140, in accordance with some embodiments. In some embodiments, a size (e.g., a width W1 or an area) of the conductive layer 510 is greater than a size (e.g., a width W2 or an area) of the chip 140. The conductive layer 510 has a thickness T3 ranging from about 5 μm to about 50 μm, in accordance with some embodiments. The wiring layer 420 has a thickness T4 ranging from about 5 μm to about 40 μm, in accordance with some embodiments.

The conductive layer 510 is used to dissipate the heat generated from the chip 140, in accordance with some embodiments. The molding layer 210 is in direct contact with the conductive layer 510 and the chip 140, in accordance with some embodiments. The conductive layer 510, the conductive via structures 174, the wiring layers 420, and the conductive pads 440 are made of the same material, in accordance with some embodiments. The conductive layer 510 is made of a conductive material, such as metal (e.g. copper, aluminum, or tungsten), in accordance with some embodiments.

FIG. 6 is a cross-sectional view of a chip package C6, in accordance with some embodiments. As shown in FIG. 6, the chip package C6 is similar to the chip package C4 of FIG. 4, except that the recess R of the chip package C6 does not extend into the substrate 172, in accordance with some embodiments. The recess R is only in the wiring structure WR1, in accordance with some embodiments.

FIGS. 7A-7B are cross-sectional views of various stages of a process for forming a chip package, in accordance with some embodiments. After the step of FIG. 1E is performed, as shown in FIG. 7A, an underfill layer 710 is formed between the interposer substrates 170 and the redistribution structure 120 and between the interposer substrates 170 and the chips 140 thereunder, in accordance with some embodiments. The underfill layer 710 is made of an insulating material, such as a polymer material or a molding compound material consisting of epoxy, fillers, resin, or combinations thereof, in accordance with some embodiments. In some other embodiments, the underfill layers 160 are not formed, and the underfill layer 710 is filled into gaps between the chips 140 and the redistribution structure 120.

As shown in FIG. 7B, the steps of FIGS. 1G-1J are performed, in accordance with some embodiments. As shown in FIG. 7B, chip packages C7 are substantially formed, in accordance with some embodiments. For the sake of simplicity, FIG. 7B only shows one of the chip packages C7, in accordance with some embodiments. The underfill layer 710 surrounds the chip 140, the underfill layer 160, the dam structure 130, the conductive structures 180, and a lower portion of the interposer substrate 170, in accordance with some embodiments.

The underfill layer 710 is in direct contact with the chip 140, the underfill layer 160, the dam structure 130, the conductive structures 180, the interposer substrate 170, and the redistribution structure 120, in accordance with some embodiments. The underfill layer 710 covers potions of sidewalls 170 s of the interposer substrate 170, in accordance with some embodiments.

The width W170 of the interposer substrate 170 is less than the width W120 of the redistribution structure 120, in accordance with some embodiments. The underfill layer 710 has an inclined sidewall 712, in accordance with some embodiments. The inclined sidewall 712 surrounds the interposer substrate 170, in accordance with some embodiments.

FIG. 8A is a cross-sectional view of a chip package C8, in accordance with some embodiments. FIG. 8B is a top view of the interposer substrate 170 of the chip package C8 of FIG. 8A, in accordance with some embodiments. As shown in FIGS. 8A and 8B, the chip package C8 is similar to the chip package C7 of FIG. 7B, except that the insulating layer 178 of the interposer substrate 170 exposes a portion of the surface 172 b of the substrate 172 of the interposer substrate 170, in accordance with some embodiments.

The interposer substrate 170 has a central region 170 c and a peripheral region 170 r surrounding the central region 170 c, in accordance with some embodiments. The exposed portion of the surface 172 b is in the peripheral region 170 r, in accordance with some embodiments. The exposed portion of the surface 172 b continuously surrounds the entire insulating layer 178, in accordance with some embodiments.

The interposer substrate 170 has an edge recess R1, in accordance with some embodiments. The edge recess R1 is surrounded by a sidewall 178 b of the insulating layer 178 and the exposed portion of the surface 172 b, in accordance with some embodiments. The edge recess R1 has a width W3 ranging from about 20 μm to about 150 μm, in accordance with some embodiments.

If, before bonding the package structure 300 to the interposer substrate 170, the underfill layer 710 extends along the sidewall 170 s (of the interposer substrate 170) onto the surface 172 b of the substrate 172, the recess R1 may accommodate the underfill layer 710 on the surface 172 b to prevent the underfill layer 710 from further extending onto the conductive pads 173 b and hindering bonding between the conductive pads 173 b and the conductive bumps 240.

The underfill layer 360 between the package structure 300 and the interposer substrate 170 fills the recess R1, in accordance with some embodiments. That is, a portion 362 of the underfill layer 360 extends into the interposer substrate 170, in accordance with some embodiments. The portion 362 has a ring shape, in accordance with some embodiments. The portion 362 continuously surrounds the entire insulating layer 178, in accordance with some embodiments. In some other embodiments, the underfill layer 360 is not formed.

FIG. 9A is a cross-sectional view of a chip package C9, in accordance with some embodiments. FIG. 9B is a top view of the interposer substrate 170 of the chip package C9 of FIG. 9A, in accordance with some embodiments. As shown in FIGS. 9A and 9B, the chip package C9 is similar to the chip package C7 of FIG. 7B, except that the insulating layer 178 of the interposer substrate 170 has a trench 178 c, in accordance with some embodiments.

The trench 178 c exposes the surface 172 b of the substrate 172 in the peripheral region 170 r, in accordance with some embodiments. The trench 178 c surrounds all of the conductive pads 173 b, in accordance with some embodiments. The trench 178 c has a width W4 ranging from about 20 μm to about 150 μm, in accordance with some embodiments.

The trench 178 c is used to accommodate the underfill layer 710 extending onto the surface 172 b to prevent the underfill layer 710 from further extending onto the conductive pads 173 b and hindering bonding between the conductive pads 173 b and the conductive bumps 240.

The underfill layer 360 between the package structure 300 and the interposer substrate 170 fills the trench 178 c, in accordance with some embodiments. That is, a portion 364 of the underfill layer 360 extends into the interposer substrate 170, in accordance with some embodiments. The portion 364 has a ring shape, in accordance with some embodiments. The portion 364 continuously surrounds all of the conductive pads 173 b, in accordance with some embodiments.

FIG. 10A is a cross-sectional view of a chip package C10, in accordance with some embodiments. FIG. 10B is a top view of the interposer substrate 170 of the chip package C10 of FIG. 10A, in accordance with some embodiments. As shown in FIGS. 10A and 10B, the chip package C10 is similar to the chip package C7 of FIG. 7B, except that the insulating layer 178 of the interposer substrate 170 has a protruding portion 178 d, in accordance with some embodiments. The protruding portion 178 d protrudes from an upper surface 178 e of the insulating layer 178, in accordance with some embodiments.

The protruding portion 178 d continuously surrounds all of the conductive pads 173 b, in accordance with some embodiments. The protruding portion 178 d has a ring shape, in accordance with some embodiments. The protruding portion 178 d extends into the underfill layer 360 between the package structure 300 and the interposer substrate 170, in accordance with some embodiments.

The protruding portion 178 d has a width W5 ranging from about 20 μm to about 150 μm, in accordance with some embodiments. The protruding portion 178 d has a thickness T ranging from about 10 μm to about 80 μm, in accordance with some embodiments. The protruding portion 178 d is used to prevent the underfill layer 710 from extending onto the conductive pads 173 b and hindering bonding between the conductive pads 173 b and the conductive bumps 240, in accordance with some embodiments.

FIG. 11 is a cross-sectional view of a chip package C11, in accordance with some embodiments. As shown in FIG. 11, the chip package C11 is similar to the chip package C7 of FIG. 7B, except that the width W6 of the interposer substrate 170 is substantially equal to or greater than the width W7 of the redistribution structure 120, in accordance with some embodiments.

The underfill layer 710 is formed between the interposer substrate 170 and the redistribution structure 120, in accordance with some embodiments. The underfill layer 710 does not extend onto the sidewall 170 s of the interposer substrate 170, in accordance with some embodiments. The underfill layer 710 has an inclined sidewall 712, in accordance with some embodiments. The inclined sidewall 712 is between the interposer substrate 170 and the redistribution structure 120, in accordance with some embodiments.

FIG. 12 is a cross-sectional view of a chip package C12, in accordance with some embodiments. As shown in FIG. 12, the chip package C12 is similar to the chip package C1 of FIG. 1J, except that the interposer substrate 170 of the chip package C12 further has conductive via structures 1210, in accordance with some embodiments.

The conductive via structures 1210 pass through the insulating layer 176, in accordance with some embodiments. The conductive via structures 1210 are connected to the conductive pads 173 a thereover and the conductive structures 180 thereunder, in accordance with some embodiments. The conductive via structures 1210 are in direct contact with the conductive structures 180 thereunder, in accordance with some embodiments.

The total thickness T5 of the substrate 172 and the insulating layer 178 ranges from about 20 μm to about 100 μm, in accordance with some embodiments. The thickness T6 of the insulating layer 176 ranges from about 30 μm to about 200 μm, in accordance with some embodiments. The total thickness T7 of the interposer substrate 170 ranges from about 50 μm to about 300 μm, in accordance with some embodiments. The recess R has a depth D1 ranging from about 30 μm to about 200 μm, in accordance with some embodiments.

The insulating layers 176 and 178 are made of different materials, in accordance with some embodiments. The insulating layer 176 is made of a polymer material, in accordance with some embodiments. The insulating layer 176 includes an Ajinomoto build-up film (ABF), in accordance with some embodiments. The insulating layer 178 is made of a polymer material, such as a solder resist material (e.g., polyimide), in accordance with some embodiments. The substrate 172 is made of an insulating material, such as a polymer material, in accordance with some embodiments.

FIG. 13 is a cross-sectional view of a chip package C13, in accordance with some embodiments. As shown in FIG. 13, the chip package C13 is similar to the chip package C1 of FIG. 1J, except that the interposer substrate 170 of the chip package C13 further has a substrate 1310, conductive via structures 1320, and solder layers 1330, in accordance with some embodiments. The recess R passes through the substrate 1310, in accordance with some embodiments. The substrate 1310 is made of a polymer material, a fiber material, a semiconductor material, a glass material, a metal material, or another suitable material.

The conductive via structures 1320 pass through the substrate 1310, in accordance with some embodiments. The conductive via structures 1320 are connected to the conductive structures 180 thereunder, in accordance with some embodiments. The substrate 1310 and the conductive via structures 1320 surround the chip 140, in accordance with some embodiments. The conductive via structures 1320 are made of a conductive material, such as copper, aluminum, or tungsten, in accordance with some embodiments.

The solder layers 1330 are between and connected to the conductive via structures 1320 and the conductive pads 173 a, in accordance with some embodiments. The solder layers 1330 are made of a solder material, such as Sn and Ag or another suitable conductive material, in accordance with some embodiments.

FIGS. 14A-14D are cross-sectional views of various stages of a process for forming a chip package, in accordance with some embodiments. After the step of FIG. 1E is performed, as shown in FIG. 14A, a trench 1410 is formed in the redistribution structure 120, in accordance with some embodiments. The trench 1410 passes through the redistribution structure 120 between the interposer substrates 170 and between the conductive structures 180 under different interposer substrates 170, in accordance with some embodiments.

The trench 1410 divides the redistribution structure 120 into portions 129, in accordance with some embodiments. The portions 129 are spaced apart from each other, in accordance with some embodiments. Each of the portions 129 is under one of the interposer substrates 170, in accordance with some embodiments. The trench 1410 is formed using a sawing process, in accordance with some embodiments.

As shown in FIG. 14A, a release film 190 is formed over the interposer substrates 170 to cover the conductive layers 179 and the conductive via structures 174, in accordance with some embodiments. Thereafter, as shown in FIG. 14A, a molding layer 210 is formed between the release film 190, the interposer substrates 170, the portions 129, and the chips 140, in accordance with some embodiments. The molding layer 210 surrounds the interposer substrates 170, the chips 140, the conductive bumps 150, the underfill layer 160, the dam structures 130, and the portions 129, in accordance with some embodiments.

As shown in FIG. 14B, the release film 190 is removed, in accordance with some embodiments. As shown in FIG. 14B, a trench 212 is formed in the molding layer 210, in accordance with some embodiments. The trench 212 passes through the molding layer 210 between the interposer substrates 170 and between the conductive structures 180 under different interposer substrates 170, in accordance with some embodiments.

The trench 212 divides the molding layer 210 into portions 214, in accordance with some embodiments. The portions 214 are spaced apart from each other, in accordance with some embodiments. Each of the portions 214 surrounds one of the interposer substrates 170 and the chip 140 and the portion 129 under the one of the interposer substrates 170, in accordance with some embodiments. The trench 212 is formed using a cutting process, in accordance with some embodiments.

As shown in FIG. 14C, the carrier substrate 110 is removed, in accordance with some embodiments. As shown in FIG. 14C, the interposer substrates 170 are flipped upside down, in accordance with some embodiments. As shown in FIG. 14C, the interposer substrates 170 are disposed over a carrier substrate 220, in accordance with some embodiments. As shown in FIG. 14C, the insulating layers 121 of the portions 129 are removed, in accordance with some embodiments.

In some embodiments, the portions 214 of the molding layer 210 adjacent to the insulating layers 121 are removed during removing the insulating layers 121. In some other embodiments (not shown), the portions 214 of the molding layer 210 adjacent to the insulating layers 121 are remained after removing the insulating layers 121. As shown in FIG. 14C, conductive bumps 230 are respectively formed over the conductive pads 122, in accordance with some embodiments. At this step, chip packages 100 are substantially formed, in accordance with some embodiments.

As shown in FIG. 14D, the carrier substrate 220 is removed, in accordance with some embodiments. As shown in FIG. 14D, the step of FIG. 1J is performed to form chip packages C14, in accordance with some embodiments. For the sake of simplicity, FIG. 14D only shows one of the chip packages C14, in accordance with some embodiments. In the chip package C14, the molding layer 210 surrounds the redistribution structure 120, in accordance with some embodiments.

FIG. 15 is a cross-sectional view of a chip package C15, in accordance with some embodiments. As shown in FIG. 15, the chip package C15 is similar to the chip package C1 of FIG. 1J, except that a top portion of the dam structure 130 of the chip package C15 extends into the recess R of the interposer substrate 170, in accordance with some embodiments.

The interposers 170 of FIGS. 7A-14D may have the wiring structures WR1 and WR2 of FIG. 4, 5 or 6. The interposers 170 of FIGS. 7A-14D may be replaced by the interposers 170 of FIGS. 2 and 4-6.

In accordance with some embodiments, chip packages and methods for forming the same are provided. The methods (for forming the chip package) bond an interposer substrate to a redistribution structure, and a chip is between the interposer substrate and the redistribution structure and is partially in the interposer substrate. The interposer substrate may decrease the warpage of a chip package (including the interposer substrate, the redistribution structure, and the chip). As a result, the bonding yield between the chip package and a package structure is improved. The interposer substrate increases stiffness and mechanical strength of the chip package. The wiring layers and the conductive pads of the interposer substrate are substantially not affected by the stress caused by thermal expansion mismatch between the molding layer and the chip of the chip package. Since the chip is partially in the interposer substrate, the total thickness of the chip package is decreased.

In accordance with some embodiments, a method for forming a chip package is provided. The method includes disposing a chip over a redistribution structure. The redistribution structure includes a first insulating layer and a first wiring layer, and the first wiring layer is in the first insulating layer and electrically connected to the chip. The method includes bonding an interposer substrate to the redistribution structure through a conductive structure. The chip is between the interposer substrate and the redistribution structure. The interposer substrate has a recess adjacent to the redistribution structure. A first portion of the chip is in the recess. The interposer substrate includes a substrate and a conductive via structure, and the conductive via structure passes through the substrate and is electrically connected to the first wiring layer through the conductive structure.

In accordance with some embodiments, a method for forming a chip package is provided. The method includes disposing a chip over a redistribution structure. The redistribution structure includes an insulating layer and a wiring layer, and the wiring layer is in the insulating layer and electrically connected to the chip. The method includes bonding an interposer substrate to the redistribution structure through a first conductive bump. The chip is between the interposer substrate and the redistribution structure. The interposer substrate has a recess adjacent to the redistribution structure, and a portion of the chip is in the recess. The method includes forming a molding layer between the interposer substrate and the redistribution structure and between the interposer substrate and the chip and surrounding the interposer substrate and the first conductive bump.

In accordance with some embodiments, a chip package is provided. The chip package includes a redistribution structure comprising an insulating layer and a wiring layer. The wiring layer is in the insulating layer. The chip package includes a chip over the redistribution structure and electrically connected to the wiring layer. The chip package includes an interposer substrate over the redistribution structure and the chip. A portion of the chip is in the interposer substrate. The chip package includes a conductive structure between the interposer substrate and the redistribution structure and electrically connected to the wiring layer.

The foregoing outlines features of several embodiments so that those skilled in the art may better understand the aspects of the present disclosure. Those skilled in the art should appreciate that they may readily use the present disclosure as a basis for designing or modifying other processes and structures for carrying out the same purposes and/or achieving the same advantages of the embodiments introduced herein. Those skilled in the art should also realize that such equivalent constructions do not depart from the spirit and scope of the present disclosure, and that they may make various changes, substitutions, and alterations herein without departing from the spirit and scope of the present disclosure. 

What is claimed is:
 1. A method for forming a chip package, comprising: disposing a chip over a redistribution structure, wherein the redistribution structure comprises a first insulating layer and a first wiring layer, and the first wiring layer is in the first insulating layer and electrically connected to the chip; and bonding an interposer substrate to the redistribution structure through a conductive structure, wherein the chip is between the interposer substrate and the redistribution structure, the interposer substrate has a recess adjacent to the redistribution structure, a first portion of the chip is in the recess, the interposer substrate comprises a substrate and a conductive via structure, and the conductive via structure passes through the substrate and is electrically connected to the first wiring layer through the conductive structure.
 2. The method for forming the chip package as claimed in claim 1, further comprising: forming an underfill layer between the interposer substrate and the redistribution structure and between the interposer substrate and the chip after bonding the interposer substrate to the redistribution structure.
 3. The method for forming the chip package as claimed in claim 1, further comprising: forming a dam structure over the redistribution structure before bonding the interposer substrate to the redistribution structure, wherein the dam structure has an opening, and the chip is over or in the opening.
 4. The method for forming the chip package as claimed in claim 1, further comprising: bonding a package structure to the interposer substrate after bonding the interposer substrate to the redistribution structure.
 5. The method for forming the chip package as claimed in claim 1, wherein the interposer substrate further comprises a first wiring structure, the substrate has a first surface facing the redistribution structure, the first wiring structure is over the first surface, the first wiring structure comprises a second insulating layer and a second wiring layer in the second insulating layer, and the recess is in the first wiring structure.
 6. The method for forming the chip package as claimed in claim 5, wherein the recess passes through the first wiring structure.
 7. The method for forming the chip package as claimed in claim 6, wherein the recess extends into the substrate.
 8. The method for forming the chip package as claimed in claim 7, wherein the substrate has a second surface facing away from the redistribution structure, the interposer substrate further comprises a second wiring structure over the second surface and the recess, the second wiring structure comprises a third insulating layer and a conductive layer in the third insulating layer, and the recess further passes through the substrate and exposes the conductive layer.
 9. The method for forming the chip package as claimed in claim 1, wherein the substrate is made of a fiber material, a polymer material, a semiconductor material, a glass material, or a metal material.
 10. A method for forming a chip package, comprising: disposing a chip over a redistribution structure, wherein the redistribution structure comprises an insulating layer and a first wiring layer, and the first wiring layer is in the insulating layer and electrically connected to the chip; bonding an interposer substrate to the redistribution structure through a first conductive bump, wherein the chip is between the interposer substrate and the redistribution structure, the interposer substrate has a recess adjacent to the redistribution structure, and a portion of the chip is in the recess; and forming a molding layer surrounding the interposer substrate and the first conductive bump, wherein the molding layer is partially between the interposer substrate and the redistribution structure and is partially between the interposer substrate and the chip and.
 11. The method for forming the chip package as claimed in claim 10, further comprising: forming the redistribution structure over a carrier substrate before disposing the chip over the redistribution structure; and removing the carrier substrate after forming the molding layer.
 12. The method for forming the chip package as claimed in claim 10, further comprising: forming a dam structure over the redistribution structure before disposing the chip over the redistribution structure, wherein the dam structure has an opening, the disposing of the chip over the redistribution structure comprises bonding the chip to the redistribution structure through a second conductive bump, and the second conductive bump is in the opening.
 13. The method for forming the chip package as claimed in claim 12, wherein a top portion of the dam structure is in the recess.
 14. The method for forming the chip package as claimed in claim 10, wherein the interposer substrate comprises a substrate, a conductive via structure, and a second wiring layer, the conductive via structure passes through the substrate and is electrically connected to the first wiring layer through the first conductive bump, the second wiring layer is in or over the substrate, and the substrate separates the second wiring layer from the molding layer and the chip.
 15. The method for forming the chip package as claimed in claim 10, further comprising: forming an adhesive layer over a top surface of the chip before bonding the interposer substrate to the redistribution structure, wherein the adhesive layer is between the chip and the interposer substrate.
 16. A chip package, comprising: a redistribution structure comprising an insulating layer and a wiring layer, wherein the wiring layer is in the insulating layer; a chip over the redistribution structure and electrically connected to the wiring layer; an interposer substrate over the redistribution structure and the chip, wherein a portion of the chip is in the interposer substrate; and a conductive structure between the interposer substrate and the redistribution structure and electrically connected to the wiring layer.
 17. The chip package as claimed in claim 16, further comprising: a package structure over the interposer substrate, wherein the package structure is electrically connected to the wiring layer of the redistribution structure through the interposer substrate.
 18. The chip package as claimed in claim 16, further comprising: an underfill layer between the chip package and the interposer substrate, wherein a portion of the underfill layer extends into the interposer substrate, and the portion has a ring shape.
 19. The chip package as claimed in claim 16, further comprising: an underfill layer between the chip package and the interposer substrate, wherein a portion of the interposer substrate extends into the underfill layer, and the portion has a ring shape.
 20. The chip package as claimed in claim 16, further comprising: a molding layer between the interposer substrate and the redistribution structure and between the interposer substrate and the chip and surrounding the interposer substrate and the conductive structure. 